Continuous milk delivery system



July 7, 1 931. c.`||. HAPGOD 1,813,238

CONTINUOUS MILK DELIVERY SYSTEM Filed Dec. 1B, 1929' n *vC-*rs maar 'a ab 7 ,5i/fwd MAJ/1 Mmofm/Lf Arm/Mfrs i UNITED STATES Patented `uly -7, 1931 PATENT ,o1-Fica CYRUS HOWARD HAPGOOD, 0F NIUTLEY, JERSEY, ASSIGNOR TO THE DE LAVAL 1 SEPARATOR COMPANY, OF NEWYYORK, N. Y., A CORPORATION OF NEW JERSEY CONTINUOUS MILK DELIVERY SYSTEM Application led December 18, 1929.- Serial No, 415,098.

The ordinary type of spitting releaser' comprises a receiving chamber and a releasing chamber. The releasing chamber is at regularintervals subjected to high and low pressure (e. g., connected alternately with air and vacuum) to permit, alternately, admission ofA milk to, and discharge of milk from, the releasing chamber. This frequent intermittent `air exhaustion involves great expenditure of power. Moreover, if the pulsations are unequal, the capacity of the releaser is cut down, and the milk in the releaser gradually accumulates,l causing flooding. Further,l ythe intermittentdis-V charge of small quantities of milk causes aeration of milk with production of foam.

The object of the present invention is the avoidance of the objections inherent in the ordinary releaser. Specifically, my objects are: avoidance of alternate air admission and exhaust except at relatively very long inter vals, the length of an interval being in inverse proportion lto the volume of milk entering the releaser; reduction to a minimum of the power required for operation; avoidance oiE aeration .and foaming; and prevention of flooding. These objects are attained in the preferred construction shown in they accompanying drawing, which iso-ne of many Y possible embodiments of the invention; the figure being an elevation, mainly in section. Instead of using a single releaser tank, I use two tanks or cans ai, ,lwhich rare or may be identical in construction and have simin lar connections with the milk supply and the pressure control valve: ,A v

The milk from therteat cups ofl any milking machine (not shown) flows through a pipe b andv thence through either branch ipe c or c', to the corresponding tank a, or

a. On the dischargeend of each branch pipe is a valve-(d or di) which opens when the corresponding tank is under suction [(partial vacuum) and closes when the corresponding tank `is under atmospheric or other relatively high absolute pressure.

`From the heads ofV `the respective tanks extend air tubes e and e to nozzles on a valve casing t.

' Mounted on the heads 'of vthe respective tanks are castingsl forming small air cham# bers j", f. Each casting has a passage connecting the air chamber withthe interior of f the corresponding tank. The chambers are closed at the top by caps g, g', which are pro# vided with constricted air passages L, h', communicating with the atmosphere.

The two air chambers f f', have nozzles which connect, by means of tubes 77, re' spectively, with nozzles on the opposite ends of the valve casing t.

Depending from the heads of the respective tanks are hangers la, c, supporting iioats m, m, which slidably engage valve stems a, a', extending into the air chambers f. The valve stems carry valvey heads 0, o, preferably of very light construction, adapted, when seated,to close air communi-v ycation between air chambers f, f, and the interiorsy of the respective tanks.

i The lower ends'of the respective tanks, if the tanks are used as releasers, are provided withdischarge nozzles' p, p, equipped with valveso, r,-which, as in ordinary releasers, close when the tanks are under vacuum and open,'under pressure of the milk, when the vacuum is released. The milk from both tanks may discharge into a common funnel s connected with any milk receiver.

In the valve casing t is areciprocable valve c. The valve casing has a centrally located nozzle w communicating with a vacuum pipe mand two atmospheric ports y and y between the vacuum port and opposite ends of the valve casing.

When valve o is in the position shown, tank ais in communication, through tube e, with vacuum port w, the interior of the tank is under vacuum, valve Z is open, and valve 7' is closed. Float m rests by gravity on its hanger. Valve oy rests on its seat by gravity and is also yheld thereon by the superior or atmospheric pressure inl pipe 'L'. Milk consequently enters the tank through ipe c and accumulates therein.

l While tank a is iilling with milk, tank a" is vin communication, through. tube e and port y', with the atmosphere. Valve cl is therefore closed and no milk enters the tank. If' there isanymilk in the tank, valve r opens and the milk discharges inte the tunnel s. Tube is under atmospheric pressure, so that valve 0 closes by its own weight.

The above described condition continues until the milk accumulating in tank a lifts float om and opens valve 0. The operation whereby this opening of the valve effected is as follows: Milk rises in tank a until float m is immersed to such depth that it floats. Continued rise of milk raises the float until it contacts with the lower end of valve stem a. At that point the float m stops, since, before it can open valve 0, it has a substantial load to overcome, namely, its own weight plus the weight of the valve plus the difference in pressure between chamber f and tank a tending to keep the valve shut. The milk continues to rise until the float is immersed to such point that its lic ing power is more than vthe weight et the float plus the weight et the valve plus ne difference in pressure tending to keep the valve closed. The valve then opens and the pressure on the top and bottom of "ne valve is equalizcd. The only necessary liliting power ot' the lieat then the .veiq'ht of the float plus the u The float then rises, carryi Thus is obtained a quick his quick opening et' v ing of valve o. 'l o gives a full vacuum in tube and the letthand chamber of cylinder t. This tends to move the piston valve o in cylinder t to the lelt. If no air was supplied to the tubn e" and the 1ight-hand hambcr el' the cyli i' valve o would move to a little past the contral point and then stop, the pressure would be equalized on both sides of the piston. Thus the valve would get on dead ceutre and become inoperative. However, the movement of valve o a snort distance to the left effects some raretica'ion of the air in the right-hand chamber cylinder t, in tube Z and in chamber with a resultant unbalancing of pressure on opposite sides of valve o. This valve being made of light a weight as is practicable and being movable independently of the float, u slight yrence in pressure, that is, a reduction in pressure in chamber f/ to but slightly below atmospheric pressure, will cause valve o to lift and allo air to flow from tank ci (which at this time is under atmospheric pressure) into chamber f and tube and the right-- hand chamber of cylinder t, thus maintaining a superior (practically atmospheric) pressure on the right-bami end of valve o until it has completed its stroke to the left.

Thereby the air pressure conditions in the two tanks are reversed. Tank a. is connected with `atmosphere through tube c and port 3.a Valve Z closes, shutting oli1 inflow of milk. Valve a opens under pressure ol the body el milk and discharges the milk into tunnel s.

On the other hand, tank a is connected with vacuum through tube e and port w. Valve al opens and milk flows into the tank. Valve 71 closes. hlilk therefore accumulates in the tank. This condition continues until the milk level rises to the height required to operate float m and valve 0. v

.ln describing the unbalancing of pressure on opposite sides of piston valve fu the el'l'ect ol" leakage et air through restricted ports /L and /l has been ignored. ln fact, these ports are not large enough te admitv air with sutlicient rapidity to materially ailect the describedshiiting oi' piston valve o from one end to t ie other ol2 cylinder' t. lf these ports were of substantial diameters, they would reduce the vacuum on the pulling end ei valve o to such an extent as to make as sured operation impossible. The only tunetion performed by these ports is to allow slow inflow of air to overcome possible leaks oi the valves and te establish and maintain atniospheric pressure at both ends of valve o during the time that a tank is filling i i h milk, thus insuring' against any tendeiicyv et valve v to shift away from its end position until it is shifted by reason of the unbalanced pressure produced by the operation of the valves o and o as hereinbeifore described.

lnstead of using tanks a and a as releasers, they may be used as ultimate containers, that is, as ordinary milk cans. ln such case they would be, oit course, unprovided with the described valved out-lets at the bottom; and upon one can being' iilled, it would be replaced by another can. llt the can should net be replaced, then, after the other can is filled, valve o will move into a neutral position and the operation will cease.

Having now fully described my invention, what l claim and desire to protect by Letters s Patent is l. A continuous milk delivery system comprising a pair of tanks, a milk inletto both tanks, a `source of suction, a pressure operated valve operable, in different positions, to connectv i'irst one tank and then the other with a source of suction, and means operable, when the milk flowing into the tank under suction reaches a predetermined level, to so imbalance the pressure on said value as to effect its movement to connect the other tank with said source of suction.

2. fr continuous milk delivery system comprising a pair of tanks, a milk inlet to both tanks, air pzussages,` a pressure operated valve adapted to control said air passages and thereby simultaneously subject either tank to a relatively high pressure and the other to a relatively low pressure, and means operable, when the milk flowing into the tank under low pressure reaches a predetermined level, to so unbalance the pressure on said valve as to effect its movement to reverse said tank pressures. l'

3. A continuous milk delivery systemcomprising a pair of tanks, tanks, air pipes oneopening into each tank, a source of suction, a pressure operated control valve adapted in one position to connect one air pipe, and disconnect the other air pipe, with suction and adapted in another position to reverse said connections, av iioat in each tank, a valve operable by each float,

and an air pipe adapted, when the last named valve is operated by the float, to open an operable face of the control valve to suction to thereby shift the valve to reverse the suction connections to the first named air pipes.

4f. lA continuous milk delivery system comprising a pair of tanks, a milk inlet to both tanks, air pipes one opening into each tank, a source of suction, a main pressure operated control valve adapted in one position to connect one air pipe with suction and the other air pipe with a source of.v higher pressure and adapted in another position to reverse said connections, air passages connected respectively with the tanks and with opposing pressure faces of the main valve, a iioat in each tank, valves betwen the tanks and the respective air passages, the last named valves being operable independently of the floats by unbalanced pneumatic pressure and being operable also b'y the corresponding floats when they accumulate sufficient energy to overcome said unbalanced pressure.

5. A continuous milk delivery system com prising a pair of tanks, a milk inlet to both tanks, a valve casing having suction and pressure ports, air pipes connectingthe respective tanks with the valve casing, a pressure operated control valve in the valve casing adapted in one position to connect one air pipe with a suction port and the other air pipe with a pressure port and adapted in another position to reverse said connections, a float in each tank, a valve operable by each float, and an air pipe adapted, when the last named valve is operated by the float, to open an operable face of the control valve tol the suction in they corresponding tank and thereby effect a shifting of the control valve from one of said positions to the other.

6. A continuous milk delivery systeml comprising a pair of tanks, a milk inlet to both tanks, air pipes one opening into each tank, a source of suction, a pressure operated control valve adapted in one position to connect one air pipe, anddisconnect the other air pipe,with suction and adaptedv in another position to reverse said connections, air chambers one `above each tank, there being an air passage from each air chamber to the corresponding tank, a valve adapted to close said passage, an air pipe connecting each air chamber with an opera milk inlet to both able face'of 'thevalve, .anda float 1in each tank adapted, when Y reaches a predetermined level, to open the last named valve and, by thus connecting said operableface of the control valve with suction, effect its shift from one of said positions to the other. Y

7..A continuousl milk 'delivery system comprising a pair of tanks, a milk inlet to kboth tanks, air pipes one opening into each tank, asource of suction, amainpressure operated ycontrol valve adapted in one position to connect one air pipe with suction andthe other air pipe with-a source of higherpressure, and adapted in another po- -the milkin the tank sition to reverse said connections, air pasf sages connected respectively with the tanks and with opposing pressure faces of the main valve, a float in each tank, valves between the tanks and the respectiveV air passages, independently of the floats by unbalanced pneumatic pressure and being operable also by the corresponding floats' when they accumulate sufficient energy to overcome said unbalanced pressure, and means providing a permanently open restricted passage through which air canflow slowly into said air passages.

8. kA continuous milk delivery system comprising a pair of tanks, a milk inlet to both tanks, air pipes one opening into each tank, a source of suction, a main pressure operated control valve adapted in one position to connect one air pipe with suction and the other air pipe with a source of higher pressure, and adapted in another position to reverse said connections, air passages connected with opposing pressure facesof the main valve and with the respective tanks, valves between the tanks andthe respective air passages and operablel by unbalanced pneumatic pressure whereby when one'tank is under suction the corresponding valve is held closed, a float in each tank movable independently of the corresponding valve but adapted, when lifted to apredetermined level by accumulating milk in a tank, to-` lift the corresponding valve and connect the corresponding air passage with suction and which the air chamber is provided with a ,i

permanently open' restricted passage allowing a relatively slow flow of air thereinto.V

10. A continuous milk delivery systemcomprising a pair of tanks, a milk inlet to both tanks, air passages, a pressure operated valve kadapted to control said air passages the last named valves being operable thereby effect movement of the valve from f and thereby simultaneously subject either tank Ato a relatively high pressure and the other to a relatively low pressure, and means operable, when the milk flowing into the 5 tank under low pressure reaches a predetermined level, to imbalance the pressure on said valve and maintain said pressure unbalanced until the valve completes the shift required to reverse and maintain reversed w Said tank pressure.

In testimony oi which invention, I have hereunto set my hand, at New York City, New York, on this 18th day of November, 1929.

15 CYRUS HOVARD HAPGGOD. 

